Semiconductor device having a plurality of semiconductor constructs

ABSTRACT

A semiconductor device includes a plurality of semiconductor constructs, each of the semiconductor constructs including a semiconductor substrate and external connection electrodes provided on an upper surface of the semiconductor substrate. The semiconductor substrates of the semiconductor constructs are different in a planar-size. The plurality of semiconductor constructs are stacked from bottom to top in descending order of planar-sizes of the semiconductor substrates included in the plurality of semiconductor constructs. An insulating film at least is provided around one semiconductor construct disposed on the top of the plurality of semiconductor constructs and on another semiconductor construct disposed under the one semiconductor construct. Each of the upper surfaces of the plurality of external connection electrodes is exposed from the one semiconductor construct and from the insulating film.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2006-002017, filed Jan. 10, 2006, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a semiconductor device in which a plurality of semiconductor constructs are stacked.

2. Description of the Related Art

In a conventional semiconductor device, a first semiconductor construct is stacked on a base board, and a second semiconductor construct having a planar-size smaller than that of the first semiconductor construct is stacked on a part of the first semiconductor construct. A plurality of external connection electrodes are provided in a peripheral area of the upper surface of the first semiconductor construct which is exposed without being covered by the second semiconductor construct, and a plurality of external connection electrodes are provided on the upper surface of the second semiconductor construct. These external connection electrodes are connected by bonding wires to respective upper layer connection pads provided on the base board around the first semiconductor construct. The first and second semiconductor constructs including the bonding wires are covered with a sealing material, and a plurality of lower layer connection pads are provided under the base board so that each of the lower layer connection pads is connected to the upper layer connection pad via a vertical conductor vertically extended in the base board. A plurality of solder balls are provided under the lower layer connection pads. A semiconductor device having such a configuration is disclosed in, for example, Jpn. Pat. Appln. KOKAI Publication No. 2005-158768.

The conventional semiconductor device described above has the following problems due to the connection by the bonding wires. That is, the diameter of the bonding wire is generally small because costs increase if the diameter of the bonding wire made of gold is relatively large, and the impedance of the bonding wire is high because the bonding wire is relatively long, which makes it impossible for the bonding wire to adapt to use at a high frequency. Further, the bonding wire hardly has heat releasing properties, and the heat releasing properties of the first and second semiconductor constructs therefore become worse. Moreover, since the base board (interposer) having the vertical conductors is used, costs increase.

BRIEF SUMMARY OF THE INVENTION

This invention is directed to provide a semiconductor device capable of reducing at least costs among the problems described above.

A semiconductor device according to a first aspect of this invention, there is provided a semiconductor device comprising:

(i) a plurality of semiconductor constructs, each of the semiconductor constructs including a semiconductor substrate and a plurality of external connection electrodes provided on an upper surface of the semiconductor substrate, the semiconductor substrates of the semiconductor constructs being different in a planar-size, the plurality of semiconductor constructs being stacked from bottom to top in descending order of planar-sizes of the semiconductor substrates included in the plurality of semiconductor constructs;

(ii) an insulating film at least provided around one semiconductor construct disposed on the top of the plurality of semiconductor constructs, and on another semiconductor construct disposed under the one semiconductor construct,

each of the upper surfaces of the plurality of external connection electrodes being exposed from the one semiconductor construct and from the insulating film.

Furthermore, a semiconductor device according to a second aspect of this invention, there is provided a semiconductor device comprising:

(i) a plurality of semiconductor constructs, each of the semiconductor constructs including a semiconductor substrate and a plurality of external connection electrodes provided on an upper surface of the semiconductor substrate, the semiconductor substrates of the semiconductor constructs being different in a planar-size, said plurality of semiconductor constructs being stacked from bottom to top in descending order of planar-sizes of the semiconductor substrates included in the plurality of semiconductor constructs;

(ii) an insulating film at least provided around one semiconductor construct disposed on the top of the plurality of semiconductor constructs, and on another semiconductor construct disposed under the one semiconductor construct; and

(iii) a plurality of upper layer wiring lines electrically connected to the plurality of external connection electrodes, respectively,

all of the plurality of upper layer wiring lines being formed on the one semiconductor construct and on the insulating film.

Still further, a semiconductor device according to a third aspect of this invention, there is provided a semiconductor device comprising:

(i) a first semiconductor construct having a first semiconductor substrate, and a plurality of first external connection electrodes provided on the first semiconductor substrate;

(ii) a second semiconductor construct having a second semiconductor substrate, a plurality of second external connection electrodes provided on the second semiconductor substrate, and a second sealing film;

the first semiconductor substrate being larger in a planar-size than the second semiconductor substrate,

the second semiconductor construct being stacked on or over the first semiconductor construct,

(iii) an insulating film provided around the second semiconductor construct and on the first semiconductor construct,

each of the upper surfaces of the plurality of second external connection electrodes penetrating the second sealing film is exposed from the second sealing film,

each of the upper surfaces of the plurality of first external connection electrodes penetrating the insulating film is exposed from the insulating film.

Further yet, a semiconductor device according to a fourth aspect of this invention, there is provided a semiconductor device comprising:

(i) a first semiconductor construct having a first semiconductor substrate, a plurality of first external connection electrodes provided on the first semiconductor substrate, and a first sealing film;

(ii) a second semiconductor construct having a second semiconductor substrate, a plurality of second external connection electrodes provided on the second semiconductor substrate, and a second sealing film;

the first semiconductor substrate being larger in a planar-size than the second semiconductor substrate, the second semiconductor construct being stacked on or over the first semiconductor construct,

all of the plurality of first external connection electrodes being formed to penetrate the first sealing film,

all of the plurality of second external connection electrodes being formed to penetrate the second sealing film,

(iii) an insulating film provided around the second semiconductor construct and on the first semiconductor construct;

(iv) a plurality of first upper layer wiring lines electrically connected to the plurality of first external connection electrodes, respectively, and formed on the insulating film; and

(v) a plurality of second upper layer wiring lines electrically connected to the plurality of second external connection electrodes, respectively, and formed on the second semiconductor construct.

According to this invention, since all the upper surfaces of the plurality of external connection electrodes are exposed on the one semiconductor construct and on the insulating film, the electrical connection wiring lines are mainly in a thickness direction of the semiconductor construct. Thus, the length of the wiring lines is reduced to make it possible to adapt to use at a high frequency. Further, heat can be released via the external connection electrodes of the semiconductor construct, so that the heat releasing properties can be improved. Moreover, costs can be reduced because a base board (interposer) having vertical conductors as heretofore used is not used.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a plan view of a semiconductor device as a first embodiment of this invention;

FIG. 2 is a sectional view along the line II-II of FIG. 1;

FIG. 3 is a sectional view of initially prepared components in one example of a method of manufacturing the semiconductor device shown in FIG. 2;

FIG. 4 is a sectional view of a step following FIG. 3;

FIG. 5 is a sectional view of a step following FIG. 4;

FIG. 6 is a sectional view of a step following FIG. 5;

FIG. 7 is a sectional view of a step following FIG. 6;

FIG. 8 is a sectional view of a step following FIG. 7;

FIG. 9 is a sectional view of a step following FIG. 8;

FIG. 10 is a sectional view of a step following FIG. 9;

FIG. 11 is a sectional view of a step following FIG. 10;

FIG. 12 is a sectional view of a semiconductor device as a second embodiment of this invention;

FIG. 13 is a sectional view of a predetermined step in one example of a method of manufacturing the semiconductor device shown in FIG. 12;

FIG. 14 is a sectional view of a step following FIG. 13;

FIG. 15 is a sectional view of a semiconductor device as a third embodiment of this invention;

FIG. 16 is a sectional view of a semiconductor device as a fourth embodiment of this invention;

FIG. 17 is a sectional view of a semiconductor device as a fifth embodiment of this invention; and

FIG. 18 is a sectional view of a semiconductor device as a six embodiment of this invention.

DETAILED DESCRIPTION OF THE INVENTION First Embodiment

FIG. 1 is a plan view of a semiconductor device as a first embodiment of this invention, and FIG. 2 is a sectional view along the line II-II of FIG. 1. This semiconductor device includes a first planar square semiconductor construct 1 a, and a second planar square semiconductor construct 1 b stacked on the first semiconductor construct 1 a. The first and second semiconductor constructs 1 aand 1 b are different in a planar-size but are much the substantially same in basic configuration, and are so-called chip size packages (CSPs) in general.

The first and second semiconductor constructs 1 aand 1 b respectively include planar square silicon substrates (semiconductor substrates) 2 a and 2 b. The planar-size of the second silicon substrate 2 b is somewhat smaller than the planar-size of the first silicon substrate 2 a. Integrated circuits (not shown) having a predetermined function are provided on the upper surfaces of the silicon substrates 2 a and 2 b, and a plurality of first and second connection pads 3 a and 3 b made of a conductive material such as an aluminum-based metal are provided in the peripheral areas of the upper surfaces of the silicon substrates 2 a and 2 b so that the respective connection pads are electrically connected to the integrated circuits.

Insulating films 4 a and 4 b made of, for example, silicon oxide are respectively provided on the upper surfaces of the first and second connection pads 3 a and 3 b except for the centers of these first and second connection pads and on the upper surfaces of the silicon substrates 2 a and 2 b. The centers of the first and second connection pads 3 a and 3 b are exposed via through holes 5 a and 5 b formed in the insulating films 4 a and 4 b. Protective films 6 a and 6 b made of, for example, a polyimide-based resin are provided all over the upper surfaces of the insulating films 4 a and 4 b. Through holes 7 a and 7 b are formed in parts of the protective films 6 a and 6 b corresponding to the through holes 5 a and 5 b of the insulating films 4 a and 4 b.

Foundation metal layers 8 a and 8 b made of a conductive material such as copper are partly provided on the upper surfaces of the protective films 6 a and 6 b. First and second wiring lines 9 a and 9 b made of a conductive material such as copper are provided all over the upper surfaces of the foundation metal layers 8 a and 8 b. Respective one ends of the foundation metal layers 8 a, 8 b extend to the first, second connection pads 3 a, 3 b via the respective holes 5 a, 5 b of the insulating films 4 a, 4 b and the holes 7 a, 7 b of the protective films 6 a, 6 b, such that the first and second wiring lines 9 a and 9 b are electrically connected to the first and second connection pads 3 a and 3 b.

First and second columnar or bump electrodes (external connection electrodes) 10 a and 10 b made of a conductive material such as copper are provided on the upper surfaces of the first and second wiring lines 9 a and 9 b. In the present specification, connection parts between the upper surfaces of the first and second wiring lines 9 a and 9 b and the first and second columnar or bump electrodes 10 a and 10 b are called electrical connection parts. The height of the first columnar electrode 10 a is somewhat larger than the height of the second columnar electrode 10 b. As shown in FIG. 1, the first columnar electrodes 10 a are arranged in one line (a plurality of lines are also possible) on four sides on the silicon substrate 2 a along these sides, and the second columnar electrodes 10 b are arranged in matrix form on the silicon substrate 2 b. Here, 3×3=9 second columnar electrodes 10 b are only shown, but this is for convenience of the figure, and ten or more second columnar electrodes 10 b are actually arranged in matrix form on all the sides. Here, the matrix form means the vertical and horizontal arrangements in a plurality of rows and columns, but also includes the arrangements in a plurality of rows and columns only in peripheral parts with nothing arranged in the center.

A second sealing film 11 b made of, for example, an epoxy-based resin is provided on the upper surfaces of the second wiring line 9 b and the protective film 6 b so that the upper surface of this sealing film is flush with the upper surface of the second columnar electrode 10 b. In this case, the upper surface of the second columnar electrode 10 b and the upper surface of the second sealing film 11 b are as high as the upper surface of the first columnar electrode 10 a of the first semiconductor construct 1 a.

Here, the first semiconductor construct 1 ais constituted of the silicon substrate 2 a, the first connection pad 3 a, the insulating film 4 a, the protective film 6 a, the foundation metal layer 8 a, the first wiring line 9 a and the first columnar electrode 10 a. The second semiconductor construct 1 b is constituted of the silicon substrate 2 b, the second connection pad 3 b, the insulating film 4 b, the protective film 6 b, the foundation metal layer 8 b, the second wiring line 9 b, the second columnar electrode 10 b and the second sealing film 11 b. It will therefore be appreciated that the first semiconductor construct 1 a does not include a film corresponding to the second sealing film 11 b of the second semiconductor construct 1 b.

The lower surface of the silicon substrate 2 b of the second semiconductor construct 1 b is adhesively bonded via an adhesive bonding layer 12 made of a die bond material to the center of the upper surface of the protective film 6 a of the first semiconductor construct 1 a, that is, an area except for an area where the first columnar electrodes 10 a are disposed. An insulating film 13 made of an insulating resin such as an epoxy-based resin is provided on the upper surface of the protective film 6 a of the first semiconductor construct 1 a and the upper surface of the first wiring line 9 a around the second semiconductor construct 1 b so that the upper surface of this insulating film 13 is flush with the upper surface of the first columnar electrode 10 a of the first semiconductor construct 1 a and the upper surface of the second sealing film 11 b of the second semiconductor construct 1 b. Solder balls 14 a and 14 b are provided on and electrically connected to the upper surfaces of the first and second columnar electrodes 10 a and 10 b of the first and second semiconductor constructs 1 a and 1 b.

As described above, in this semiconductor device, the second semiconductor construct 1 b having a planar-size somewhat smaller than that of the first semiconductor construct 1 a is stacked and provided in the center of the upper surface of the first semiconductor construct 1 a, and the insulating film 13 is provided on the first semiconductor construct 1 a around the second semiconductor construct 1 b, and then the solder balls 14 a and 14 b are respectively provided on the first and second columnar or bump electrodes 10 a and 10 b of the first and second semiconductor constructs 1 a and 1 b. Thus, the electrical connection wiring lines are mainly in a thickness direction of the first and second semiconductor constructs 1 a and 1 b, such that the length of the wiring lines is reduced to make it possible to adapt to use at a high frequency.

Furthermore, heat can be released to the outside via the first and second columnar electrodes 10 a and 10 b of the first and second semiconductor constructs 1 a and 1 b and via the solder balls 14 a and 14 b provided thereon, so that heat releasing properties can be improved. Moreover, costs can be reduced because a base board (interposer) having vertical conductors as heretofore used is not used.

Next, one example of a method of manufacturing this semiconductor device will be described. First, as shown in FIG. 3, an assembly is prepared in which the first connection pad 3 a made of, for example, an aluminum-based metal, the insulating film 4 a made of, for example, silicon oxide, and the protective film 6 a made of, for example, a polyimide-based resin are provided on the silicon substrate 2 a in a wafer state, and the center of the first connection pad 3 a is exposed via the hole 5 a and 7 a formed in the insulating film 4 a and the protective film 6 a.

In this case, integrated circuit of circuits (not shown) having a predetermined function are formed in areas of the upper surface of the silicon substrate 2 a in the wafer state where the first semiconductor constructs 1 a are formed, and the first connection pads 3 a formed in peripheral parts of these areas are electrically connected to the integrated circuits formed in the corresponding areas. Further, the thickness of the silicon substrate 2 a in the wafer state is somewhat larger than the thickness of the silicon substrate 2 a shown in FIG. 2.

Next, as shown in FIG. 4, the foundation metal layer 8 a (strictly speaking, this is a layer for forming a foundation metal layer 8 a, but is referred to as the foundation metal layer in the present invention to make the explanation easier to understand) is formed on the upper surface of the first connection pads 3 a exposed via the holes 5 a and 7 a of the insulating film 4 a and all over the upper surface of the protective film 6 a. In this case, the foundation metal layer 8 a may only be a copper layer formed by electroless plating, may only be a copper layer formed by sputtering, or may be a multilayer formed by sputtering, a copper layer on a thin film layer such as titanium formed by sputtering, for example. It will be appreciated that the materials to form these layers and various conductive layers, metal layers and wiring lines described below are not limited to copper, and may be conductive materials other than copper.

Next, a plating resist film 21 is patterned/formed formed on the upper surface of the foundation metal layer 8 a (a film is formed, and then patterned into a predetermined shape). In this case, an opening 22 is formed in the plating resist film 21 in a part corresponding to an area where the first wiring line 9 a is formed. Then, electrolytic plating with copper is carried out using the foundation metal layer 8 a as a plating current path, thereby forming the first wiring line 9 a on the upper surface of the foundation metal layer 8 a in the opening 22 of the plating resist film 21. Then, the plating resist film 21 is removed.

Next, as shown in FIG. 5, a plating resist film 23 is patterned/formed on the upper surfaces of the first wiring line 9 a and the foundation metal layer 8 a. In this case, an opening 24 is formed in the plating resist film 23 in a part corresponding to an area where the first columnar electrode 10 a is formed. Then, electrolytic plating with copper is carried out using the foundation metal layer 9 a as a plating current path, thereby forming the first columnar electrode 10 a on the upper surface of the electrical connection portion of the first wiring line 9 a in the opening 24 of the plating resist film 23.

Subsequently, the plating resist film 23 is removed, and then unnecessary portions of the foundation metal layer 8 a are removed by a selectively etching process using the first wiring line 9 a as a mask, whereby the foundation metal layer 8 a remains under the first wiring line 9 a alone, as shown in FIG. 6. In this state, in the area on the silicon substrate 2 a in the wafer state where each of the first semiconductor constructs 1 a is formed, there are formed the first connection pads 3 a, the insulating film 4 a, the protective film 6 a, the foundation metal layer 8 a, the first wiring lines 9 a and the first columnar electrodes 10 a that constitute the first semiconductor construct 1 a.

There are prepared a plurality of materials in which the adhesive bonding layers 12 are provided on the lower surfaces of the silicon substrates 2 b of the second semiconductor constructs 1 b. In this case, the second semiconductor constructs 1 b having the adhesive bonding layers 12 can be obtained as follows: the integrated circuits (not shown) having the predetermined function, the second connection pads 3 b, the insulating film 4 b, the protective film 6 b, the foundation metal layers 8 b, the second wiring lines 9 b, the second columnar electrodes 10 b and the second sealing film 11 b are formed on the silicon substrate 2 b in the wafer state; and the adhesive bonding layer 12 made of a die bond material such as an epoxy-based resin commercially available as a die attachment film is then fixedly attached in a semi-hardened state by heating and pressurization to the lower surface of the silicon substrate 2 b in the wafer state; and finally this assembly is divided into pieces by dicing.

Next, as shown in FIG. 7, the adhesive bonding layers 12 fixedly attached to the lower surfaces of the silicon substrates 2 b of a plurality of semiconductor constructs 1 b are adhesively bonded to the centers of the areas on the upper surface of the protective film 6 a on the silicon substrate 2 a in the wafer state where the first semiconductor constructs 1 a are formed. The adhesive bonding here is achieved by the full hardening of the adhesive bonding layers 12 through heating and pressurization. Here, the height of the first columnar electrode 10 a of the first semiconductor construct 1 a is set to be about 0.01 to 0.07 mm higher than the upper surface of the second sealing film 11 b of the second semiconductor construct 1 b. By way of example, if the thickness of the second semiconductor construct 1 b is 0.12 mm, the height of the first columnar electrode 10 a of the first semiconductor construct 1 a (strictly speaking, a height including the foundation metal layer 8 a and the wiring line 9 a) is 0.15 mm.

Next, as shown in FIG. 8, by a method such as a screen printing method, a spin coat method or a die coat method, the insulating film or layer 13 made of, for example, an epoxy-based resin is formed on the upper surfaces of the first columnar electrodes 10 a, the protective film 6 a and the second semiconductor construct 1 b so that the thickness of this insulating film 13 is larger than the height of the first columnar electrode 10 a. Thus, in this state, the upper surface of the first columnar electrodes 10 a and the upper surface of the second semiconductor construct 1 b are covered by the top of the insulating film 13.

Next, the upper surface sides of the insulating film 13 and the first columnar electrodes 10 a are properly polished, so that, as shown in FIG. 9, the upper surfaces of the second columnar electrodes 10 b of the second semiconductor construct 1 b, the upper surface of the second sealing film 11 b and the upper surfaces of the first columnar electrodes 10 a are exposed, and the upper surface of the insulating film 13, the exposed upper surfaces of the first and second columnar electrodes 10 a and 10 b, and the exposed second sealing film 11 b are flattened in the same plane.

Next, as shown in FIG. 10, the lower surface side of the silicon substrate 2 a in the wafer state is properly polished to reduce the thickness of the silicon substrate 2 a in the wafer state. Then, as shown in FIG. 11, the solder balls 14 a and 14 b are formed or bonded on the upper surfaces of the first and second columnar electrodes 10 a and 10 b. Subsequently, the second semiconductor constructs 1 b are separated from each other by a dicing step, thereby obtaining a plurality of semiconductor devices shown in FIG. 2.

Second Embodiment

FIG. 12 is a sectional view of a semiconductor device as a second embodiment of this invention. This semiconductor device is different from the semiconductor device shown in FIG. 2 in that a semiconductor construct having no second sealing film 11 b is used in a second semiconductor construct 1 b, and in that an insulating film 13 is directly provided on the upper surface of a protective film 6 b including a second wiring line 9 b so that the upper surface of this insulating film 13 is flush with the upper surfaces of second columnar or bump electrodes 10 b.

Next, one example of a method of manufacturing this semiconductor device will be described. First, after the step shown in FIG. 6, adhesive bonding layers 12 fixedly attached to the lower surfaces of silicon substrates 2 b of a plurality of semiconductor constructs 1 b are adhesively bonded to the centers of the areas on the upper surface of a protective film 6 a on a silicon substrate 2 a in a wafer state where first semiconductor constructs 1 a are formed, shown in FIG. 13. In this case, the semiconductor constructs 1 b have no second sealing film 11 b shown in FIG. 7. Moreover, the height of the second columnar electrode 10 b of the second semiconductor construct 1 b is somewhat larger than that in the case shown in FIG. 7, and is about the same as the height of a first columnar or bump electrode 10 a of each of the first semiconductor constructs 1 a.

Next, as shown in FIG. 14, by a method such as a screen printing method, a spin coat method or a die coat method, the insulating film or layer 13 made of, for example, an epoxy-based resin is formed on the upper surfaces of the protective film 6 a, the second columnar electrodes 10 b, the protective film 6 b, and the second columnar electrodes 10 b of the second semiconductor construct 1 b so that the thickness of this insulating film 13 is larger than the height of the first and second columnar electrodes 10 a and 10 b. Thus, in this state, the upper surfaces of the first and second columnar electrodes 10 a and 10 b are covered by the upper part of the insulating film 13. Subsequently, as in the first embodiment, the upper surface sides of the insulating film 13, etc. are polished, an then the lower surface side of the silicon substrate 2 a is polished, solder balls 14 a and 14 b are formed, and dicing is carried out, thereby obtaining a plurality of semiconductor devices shown in FIG. 12.

Third Embodiment

FIG. 15 is a sectional view of a semiconductor device as a third embodiment of this invention. The great differences between this semiconductor device and the semiconductor device shown in FIG. 2 are that a semiconductor construct having a first sealing film 11 a is used as a first semiconductor construct 1 a, and that first and second upper layer wiring lines 17 a and 17 b, upper layer columnar or bump electrodes (third columnar electrodes) 18 a and 18 b, an overcoat film 19, solder balls 14 a and 14 b, etc. are provided on a second semiconductor construct 1 b and an insulating film 13.

That is, the first semiconductor construct 1 a has a structure in which the first sealing film 11 a is provided on the upper surfaces of a protective film 6 a and first wiring lines 9 a so that the upper surface of the first sealing film 11 a is flush with the upper surfaces of first columnar electrodes 10 a. In this case, the height of the first columnar electrode 10 a is somewhat smaller than the height of the first columnar electrode 10 a shown in FIG. 2.

The lower surface of a silicon substrates 2 b of the second semiconductor construct 1 b is adhesively bonded via an adhesive bonding layer 12 to the center of the upper surface of the first sealing film 11 a. The insulating film or layer 13 is provided on the upper surfaces of the third sealing film 11 a and the first columnar electrodes 10 a of the first semiconductor construct 1 a around the second semiconductor construct 1 b so that the upper surface of the insulating film 13 is flush with the upper surface of the second sealing film 11 b of the second semiconductor construct 1 b. In this case, vertical through holes 15 a are formed in the insulating film 13 in parts corresponding to the centers of the upper surfaces of the first columnar electrodes 10 a of the first semiconductor construct 1 a.

Upper layer foundation metal layers 16 a and 16 b made of, for example, copper are respectively provided on the upper surfaces of the insulating film 13 and the second sealing film 11 b. The first and second upper layer wiring lines 17 a and 17 b made of copper are provided all over the upper surfaces of the upper layer foundation metal layers 16 a and 16 b. One end of the first upper layer wiring line 17 a is connected to the upper surface of the first columnar electrode 10 a of the first semiconductor construct 1 a via the hole 15 a formed through the insulating film 13, so that the upper layer foundation metal layer 16 a is electrically connected to the first columnar electrode 10 a. One end of the upper layer foundation metal layer 16 b is connected to the upper surface of the second columnar electrode 10 b of the second semiconductor construct 1 b, so that the second upper layer wiring line 17 b is electrically connected to the electrode 10 b.

The upper layer columnar or bump electrodes 18 a and 18 b made of copper are respectively provided on the upper surfaces of the first and second upper layer wiring lines 17 a and 17 b, and parts of the upper surfaces of the first and second upper layer wiring lines 17 a and 17 b connected to the upper layer columnar electrodes 18 a and 18 b are called electrical connection parts. The overcoat film 19 made of, for example, an epoxy-based resin is provided on the upper surfaces of the second sealing film 11 b, the insulating film 13, the first and second upper layer wiring lines 17 a and 17 b so that the upper surface of this overcoat film 19 is flush with the upper surfaces of the upper layer columnar electrodes 18 a and 18 b in the same plane. The solder balls 14 a and 14 b are respectively provided on the upper surfaces of the upper layer columnar electrodes 18 a and 18 b.

Next, in connection with this semiconductor device, a case will be described where the through hole 15 a is formed in the insulating film 13. For example, as shown in FIG. 9, the upper surface of the second sealing film 11 b including the upper surface of the second columnar electrode 10 b of the second semiconductor construct 1 b is exposed by polishing, and the upper surface of the insulating film 13 including the exposed upper surfaces of the first columnar electrode 10 a and the second sealing film 11 b is flattened in the same plane, and then the hole 15 a is formed in the insulating film 13 in part corresponding to the center of the upper surface of the first columnar electrode 10 a of the first semiconductor construct 1 a by laser processing in which a laser beam is applied or by a photolithographic method.

Fourth Embodiment

FIG. 16 shows a sectional view of a semiconductor device as a fourth embodiment of this invention. This semiconductor device is different from the semiconductor device shown in FIG. 15 in that the upper surface of a second semiconductor construct 1 b is covered with a part of an insulating film 13, in that a through hole 15 b is formed in the insulating film 13 in a part corresponding to the center of the upper surface of a second columnar electrode 10 b of the second semiconductor construct 1 b, and in that one end of an upper layer foundation metal layer 16 b is connected to the upper surface of the second columnar electrode 10 b of the second semiconductor construct 1 b via the hole 15 b formed through the insulating film 13, so that a second upper layer wiring line 17 b is electrically connected to the second columnar electrode 10 b.

Next, in connection with this semiconductor device, a case will be described where the holes 15 a and 15 b are formed in the insulating film 13. For example, as shown in FIG. 8, the insulating film 13 is formed to cover the upper surface of the second semiconductor construct 1 b, and then the holes 15 a and 15 b are formed in the insulating film 13 in parts corresponding to the centers of the upper surfaces of the first and second columnar electrodes 10 a and 10 b of the first and second semiconductor constructs 1 a and 1 b by laser processing in which a laser beam is applied or by a photolithographic method.

Fifth Embodiment

FIG. 17 shows a sectional view of a semiconductor device as a fifth embodiment of this invention. This semiconductor device is different from the semiconductor device shown in FIG. 15 in that this semiconductor device does not have upper layer columnar electrodes 18 a and 18 b, in that an overcoat film 19 is formed by, for example, a solder resist, in that vertical through holes 20 a and 20 b are formed in the overcoat film 19 in parts corresponding to the electrical connection parts of first and second upper layer wiring lines 17 a and 17 b, and in that solder balls 14 a and 14 b are provided in and above the holes 20 a and 20 b so that these solder balls 14 a and 14 b are connected to the electrical connection parts of the first and second upper layer wiring lines 17 a and 17 b.

Sixth Embodiment

While the cases have been described in the above embodiments where two semiconductor constructs are stacked, three or more semiconductor constructs may be stacked, and, for example, three semiconductor constructs may be stacked as in a sixth embodiment of this invention shown in FIG. 18. The great differences between this semiconductor device and the semiconductor device shown in FIG. 2 are that a first semiconductor construct 1 a is stacked via an adhesive bonding layer 12 ain the center on an undermost layer semiconductor construct 1 c having a planar-size (dimensions along a planar surface) larger than that of the first semiconductor construct 1 a and having a structure similar to that of the first semiconductor construct 1 a, that a second semiconductor construct 1 b is stacked in the center on the first semiconductor construct 1 a via an adhesive bonding layer 12 b, and that an insulating film 13 is provided on the undermost layer semiconductor construct 1 c and the first semiconductor construct 1 a around the second semiconductor construct 1 b.

While the first columnar electrodes 10 a of the first semiconductor construct 1 a are arranged in only one column or row around the second semiconductor construct 1 b in the configurations shown in the embodiments described above, the first columnar electrodes 10 a may be arranged in a plurality of columns or rows around the second semiconductor construct 1 b. Moreover, while the first columnar electrode 10 a of the first semiconductor construct 1 a is connected to the first connection pad 3 a via the foundation metal layer 8 a and the first wiring line 9 a formed on the first connection pad 3 a and the protective film 6 a in the shown configurations, each of the first columnar electrodes 10 a may be formed on the first connection pad 3 a directly or with a foundation metal layer for adhesive bonding and/or for a barrier interposed therebetween.

In the present invention, a number of semiconductor constructs, each including a semiconductor substrate is not limited, and may be two or more, wherein semiconductor constructs being stacked from bottom to top in descending order of planar-sizes of the semiconductor substrates included in the plurality of semiconductor constructs. 

1. A semiconductor device comprising: (i) a plurality of semiconductor constructs, each of the semiconductor constructs including a semiconductor substrate and a plurality of external connection electrodes provided on an upper surface of the semiconductor substrate, the semiconductor substrates of the semiconductor constructs being different in a planar-size, the plurality of semiconductor constructs being stacked from bottom to top in descending order of planar-sizes of the semiconductor substrates included in the plurality of semiconductor constructs; (ii) an insulating film at least provided around one semiconductor construct disposed on the top of the plurality of semiconductor constructs and on another semiconductor construct disposed under the one semiconductor construct, each of the upper surfaces of the plurality of external connection electrodes being exposed from the one semiconductor construct and from the insulating film.
 2. The semiconductor device according to claim 1, wherein said another semiconductor construct includes the plurality of external connection electrodes in a peripheral portion of an upper surface thereof; and said one semiconductor construct is provided in an area on the another semiconductor construct where the plurality of external connection electrodes are not disposed.
 3. The semiconductor device according to claim 2, wherein each of the plurality of external connection electrodes of said another semiconductor construct includes one first bump electrode; and said insulating film is provided to cover outer peripheral surfaces of the plurality of first bump electrodes.
 4. The semiconductor device according to claim 3, wherein each of the plurality of external connection electrodes of said one semiconductor construct includes one second bump electrode; the one semiconductor construct includes a second sealing film provided to cover outer peripheral surfaces of the plurality of second bump electrodes; and the insulating film is provided around the one semiconductor construct.
 5. The semiconductor device according to claim 3, wherein each of the plurality of external connection electrodes of said one semiconductor construct includes one second bump electrode; and the insulating film is provided to cover outer peripheral surfaces of the plurality of second bump electrodes.
 6. The semiconductor device according to claim 3, wherein a solder ball is provided on each of the first and second bump electrodes.
 7. A semiconductor device comprising: (i) a plurality of semiconductor constructs, each of the semiconductor constructs including a semiconductor substrate and a plurality of external connection electrodes provided on an upper surface of the semiconductor substrate, the semiconductor substrates of the semiconductor constructs being different in a planar-size, said plurality of semiconductor constructs being stacked from bottom to top in descending order of planar-sizes of the semiconductor substrates included in the plurality of semiconductor constructs; (ii) an insulating film at least provided around one semiconductor construct disposed on the top of the plurality of semiconductor constructs, and on another semiconductor construct disposed under the one semiconductor construct; and (iii) a plurality of upper layer wiring lines electrically connected to the plurality of external connection electrodes, respectively, all of the plurality of upper layer wiring lines being formed on the one semiconductor construct and on the insulating film.
 8. The semiconductor device according to claim 7, wherein said another semiconductor construct includes the plurality of external connection electrodes in a peripheral portion of an upper surface thereof; and said one semiconductor construct is provided in an area on the another semiconductor construct where the plurality of external connection electrodes are not disposed.
 9. The semiconductor device according to claim 8, wherein each of the plurality of external connection electrodes of said another semiconductor construct includes a first bump electrode; said another semiconductor construct has a first sealing film provided to cover outer peripheral surfaces of the plurality of first bump electrodes; and each of the plurality of first upper layer wiring lines among said plurality of upper layer wiring lines, electrically connected to the plurality of external connection electrodes of said another semiconductor construct is provided to be connected to an upper surface of one of the plurality of first bump electrodes via one of a plurality of holes provided in the insulating film.
 10. The semiconductor device according to claim 9, wherein each of the plurality of external connection electrodes of said one semiconductor construct includes a second bump electrode; and each of the plurality of second upper layer wiring lines among the plurality of upper layer wiring lines, electrically connected to the plurality of external connection electrodes of said one semiconductor construct is provided on the one semiconductor construct to be connected to an upper surface of one of the plurality of second bump electrodes.
 11. The semiconductor device according to claim 9, wherein each of the plurality of external connection electrodes of said one semiconductor construct includes one second bump electrode; the insulating film is provided to cover the plurality of second bump electrodes; and each of the plurality of second upper layer wiring lines among the plurality of upper layer wiring lines, electrically connected to the plurality of external connection electrodes of said one semiconductor construct is provided on the insulating film to be connected to an upper surface of the bump electrode of said one semiconductor construct via one of a plurality of holes provided in the insulating film.
 12. The semiconductor device according to claim 9, further comprising: a plurality of third bump electrodes provided to be electrically connected to electrical connection parts of the plurality of upper layer wiring lines, respectively; and an overcoat film provided to cover outer peripheral surfaces of the plurality of third bump electrodes.
 13. The semiconductor device according to claim 12, wherein a solder ball is provided on each of the third columnar electrodes.
 14. The semiconductor device according to claim 9, comprising: an overcoat film covering the plurality of upper layer wiring lines without covering the electrical connection parts thereof.
 15. The semiconductor device according to claim 14, wherein a solder ball is provided on each of the electrical connection parts of the plurality of upper layer wiring lines.
 16. The semiconductor device according to claim 3, wherein each of the plurality of external connection electrodes of said another semiconductor construct further includes one first connection pad, and one wiring line connecting the one first connection pad and one of the plurality of first bump electrodes.
 17. The semiconductor device according to claim 9, wherein each of the plurality of external connection electrodes of said another semiconductor construct further includes one first connection pad, and one wiring line connecting the one first connection pad and one of the plurality of first bump electrodes.
 18. The semiconductor device according to claim 4, wherein each of the plurality of external connection electrodes of the one semiconductor construct further includes one second connection pad, and one second wiring line connecting the one second connection pad and one of the plurality of second bump electrodes.
 19. The semiconductor device according to claim 10, wherein each of the plurality of external connection electrodes of the one semiconductor construct further includes one second connection pad, and one second wiring line connecting the one second connection pad and one of the plurality of second bump electrodes.
 20. A semiconductor device comprising: (i) a first semiconductor construct having a first semiconductor substrate, and a plurality of first external connection electrodes provided on the first semiconductor substrate; (ii) a second semiconductor construct having a second semiconductor substrate, a plurality of second external connection electrodes provided on the second semiconductor substrate, and a second sealing film; the first semiconductor substrate being larger in a planar-size than the second semiconductor substrate, the second semiconductor construct being stacked on or over the first semiconductor construct, (iii) an insulating film provided around the second semiconductor construct and on the first semiconductor construct, each of the upper surfaces of the plurality of second external connection electrodes penetrating the second sealing film is exposed from the second sealing film, each of the upper surfaces of the plurality of first external connection electrodes penetrating the insulating film is exposed from the insulating film.
 21. A semiconductor device comprising: (i) a first semiconductor construct having a first semiconductor substrate, a plurality of first external connection electrodes provided on the first semiconductor substrate, and a first sealing film; (ii) a second semiconductor construct having a second semiconductor substrate, a plurality of second external connection electrodes provided on the second semiconductor substrate, and a second sealing film; the first semiconductor substrate being larger in a planar-size than the second semiconductor substrate, the second semiconductor construct being stacked on or over the first semiconductor construct, all of the plurality of first external connection electrodes being formed to penetrate the first sealing film, all of the plurality of second external connection electrodes being formed to penetrate the second sealing film, (iii) an insulating film provided around the second semiconductor construct and on the first semiconductor construct; (iv) a plurality of first upper layer wiring lines electrically connected to the plurality of first external connection electrodes, respectively, and formed on the insulating film; and (v) a plurality of second upper layer wiring lines electrically connected to the plurality of second external connection electrodes, respectively, and formed on the second semiconductor construct. 